Surfactant type efficient dispersing agent for TC4 titanium alloy powder and application of surfactant type efficient dispersing agent

Abstract

The invention discloses a surfactant type efficient dispersing agent for TC4 titanium alloy powder and application of the surfactant type efficient dispersing agent, and belongs to the technical field of metal powder preparation. Through the synergistic effect of an alcohol solvent, an anionic surfactant and an auxiliary dispersant, the dispersant is composed of the following components in percentage by mass: 70%-85% of the alcohol solvent, 0.2%-0.4% of the anionic surfactant and 14.6%-29.8% of the auxiliary dispersant, and the average molecular weight of the auxiliary dispersant is 300-2500. The preparation method of the dispersing agent comprises the steps that TC4 coarse powder obtained after hydrogenation, dehydrogenation and crushing, stainless steel grinding balls and the dispersing agent are put into a ball milling tank to be subjected to wet planetary ball milling, the adding amount of the dispersing agent accounts for 150%-250% of the mass of the coarse powder, the mass ratio of the materials to the balls is 3.5: 1-4.5: 1, and after ball milling, solid-liquid separation and two-stage vacuum drying are conducted to obtain a finished product. According to the method, powder spheroidization can be effectively promoted, the sphericity degree of the obtained powder is larger than 0.9, the Hall flow velocity is smaller than or equal to 38 s / 50 g, the oxygen content is smaller than or equal to 0.2%, and the strict requirement of high-end additive manufacturing for powder performance is met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of metal powder preparation, and particularly relates to a surface-active high-efficiency dispersant for TC4 titanium alloy powder and application thereof. BACKGROUND

[0002] Titanium alloy, especially TC4 alloy, has become an indispensable key material in the fields of aerospace, biomedical and high-end equipment manufacturing due to its high strength, low density and excellent corrosion resistance. In recent years, metal additive manufacturing technology represented by laser selective melting has put forward extremely strict standards for the quality of raw metal powder. The ideal printing powder not only needs to have a high degree of sphericity to ensure good flowability and uniformity of powder laying, but also needs to have a concentrated particle size distribution to ensure the density and surface finish of the printed part, and the content of interstitial elements such as oxygen, nitrogen and carbon must be controlled at a very low level to ensure the mechanical properties of the final component.

[0003] At present, the mainstream method for preparing TC4 titanium alloy powder in industry is gas atomization. However, the powder obtained by simple gas atomization often has problems such as satellite ball adhesion, wide particle size distribution and hollow powder, which is difficult to directly meet the needs of high-end applications. Therefore, the industry generally adopts the process route of gas atomization combined with subsequent treatment. Among them, the hydrogenation-dehydrogenation method is an effective means of powder refinement, which can break the gas atomized coarse powder and obtain finer raw material. However, the powder treated by this method is extremely irregular in shape, with sharp corners, and has very poor flowability, so it must be shaped by ball milling process to obtain nearly spherical particles.

[0004] Wet planetary ball milling is a key process for powder shaping. In this process, the dispersant plays a crucial role, which directly affects the dispersion state of powder particles in the liquid phase, the efficiency of ball milling shaping and the chemical purity of the final product. However, when this process is applied to TC4 titanium alloy powder which is active and easy to oxidize, the existing technology faces several deep-seated and interrelated problems.

[0005] Firstly, the nature of TC4 material itself brings inherent difficulties to ball milling shaping. Titanium alloy has high surface energy and strong chemical activity. The fresh surface generated under the action of mechanical force in ball milling has a strong adhesion tendency. Particles are prone to cold welding and agglomeration rather than ideal plastic deformation and rolling friction to form spherical particles. Once this hard agglomeration is formed, it will not only significantly reduce the ball milling efficiency, leading to unqualified sphericity, but also become a defect source in subsequent screening and use, seriously affecting the flowability of the powder and the stability of the printing process.

[0006] Secondly, the existing general ball milling medium and dispersant scheme is seriously insufficient for TC4 powder, and cannot balance the contradiction between morphology control and purity control. The commonly used scheme, such as using pure alcohol such as anhydrous ethanol as a grinding medium, mainly provides cooling and prevents environmental oxidation, but has limited effect on reducing powder surface energy and preventing soft agglomeration caused by van der Waals force between fine particles, and has insufficient contribution to promoting spheroidization. While some water-based or ionic dispersants borrowed from other industrial fields, although they can improve dispersion through electrostatic repulsion, their composition can introduce impurity ions that are difficult to clean, or cause more serious particle bridging and hard agglomeration due to capillary force in the subsequent drying process. More importantly, these dispersants are not designed for the needs of TC4 powder in the specific high-energy environment of planetary ball milling, and their molecular structure, adsorption strength on the powder surface, retention ability under mechanical impact, and whether they can be completely removed at the end, all lack targeted considerations, resulting in unstable and unpredictable process effects.

[0007] Finally, the most critical problem is that there is a severe lack of high-efficiency surfactant-type dispersants designed specifically for TC4 titanium alloy wet ball milling shaping in the market. Although there are a variety of dispersants in the fields of ceramic slurry and pigment suspension, their chemical composition, mechanism of action and applicable environment are fundamentally different from the scenario of TC4 ball milling. These dispersants either cannot form a firm and effective adsorption with TC4 surface and are easily desorbed and fail during intense ball milling, or their molecular chain structure cannot form a thick and stable steric hindrance layer on the particle surface, which cannot inhibit secondary agglomeration under high-energy collision, or they contain or decompose oxygen, carbon and other impurity elements during the process, polluting the titanium alloy powder which has extremely high purity requirements. The disclosed TC4 titanium alloy ball milling dispersants in the prior art are mostly binary systems, which have the defects of insufficient dispersion stability and difficulty in breaking through 0.85 in powder sphericity, and cannot meet the stringent requirements of high-end additive manufacturing. In addition, some of the existing TC4 powder drying processes use air atmosphere drying, which increases the oxygen content of the powder to more than 0.25%, further limiting the application of the powder in high-end fields. Therefore, developing a special dispersant that can deeply wet TC4 powder, achieve long-term stable dispersion through multiple synergistic effects, and be completely cleaned and removed without harmful residues in subsequent processes, has become a key technical requirement to break through the bottleneck of TC4 printing powder preparation and improve product consistency and reliability. SUMMARY

[0008] The purpose of the present application is to provide a surfactant-type high-efficiency dispersant for TC4 titanium alloy powder and its application.

[0009] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions: A surface active agent type high-efficiency dispersant for TC4 titanium alloy powder, which comprises the following components: alcohol solvent: 70%-85%; anionic surfactant selected from stearic acid, oleic acid or sodium dodecyl benzene sulfonate: 0.2%-0.4%; co-dispersant selected from paraffin, petroleum ether, polyethylene glycol or polyethylene wax: 14.6%-29.8%, and the average molecular weight of the co-dispersant is 300-2500.

[0010] Further, the alcohol solvent is one of isopropyl alcohol, ethanol or methanol, and the mass percentage thereof is 70%-85%.

[0011] Further, the co-dispersant is paraffin, petroleum ether, polyethylene glycol or polyethylene wax, and the average molecular weight of the co-dispersant is 86-500.

[0012] Application of a surface active agent type high-efficiency dispersant for TC4 titanium alloy powder in preparation of TC4 titanium alloy powder by wet planetary ball milling.

[0013] A preparation method of a quasi-spherical TC4 titanium alloy powder, comprising the following steps: (1) placing hydrogenated and dehydrogenated broken TC4 titanium alloy coarse powder, stainless steel grinding balls and the dispersant as claimed in any one of claims 1 to 3 together in a ball mill jar of a planetary ball mill for wet ball milling, wherein the addition amount of the dispersant is 150%-250% of the mass of the TC4 titanium alloy coarse powder, the mass ratio of the stainless steel grinding balls to the TC4 titanium alloy coarse powder is 3:1-5:1, the diameter of the stainless steel grinding balls is 5mm-15mm, and the mass ratio of different diameter grinding balls is 1:2:3-3:2:1; (2) after the ball milling is completed, performing solid-liquid separation on the material in the ball mill jar to obtain a solid powder; (3) performing two-stage drying on the solid powder under vacuum conditions, the first-stage drying temperature is 60-80℃, and the second-stage drying temperature is 80-120℃, wherein the vacuum degree is ≤1×10 -2 Pa.

[0014] Further, the process conditions of the wet ball milling are as follows: the ball milling rotation speed is 80-240r / min, and the ball milling time is 1-4 hours.

[0015] Further, the wet ball milling is performed in an intermittent manner, specifically, the ball milling is operated for 10-60 minutes and then paused for 2-10 minutes.

[0016] Further, the stainless steel grinding balls are composed of at least two kinds of grinding balls with different diameters.

[0017] Further, the first stage drying time is 2-12 hours, and the second stage drying time is 1-8 hours.

[0018] Further, the particle size of the hydrogenated-dehydrogenated broken TC4 titanium alloy coarse powder is 45-200 mu m.

[0019] Advantages: 1. The surface active agent type high-efficiency dispersant realizes efficient dispersion and sphericalization promotion of the TC4 titanium alloy powder in the ball milling process. The dispersant system is not a simple use of single components, but a scientific compounding of alcohol solvents, specific anionic surfactants and dispersant aids, which constructs a synergistic mechanism. Among them, the anionic surfactant can be anchored on the surface of the TC4 powder with its polar group, and its lipophilic long chain greatly reduces the solid-liquid interfacial tension, enhances the wetting and wrapping of the liquid to the powder, and makes the initial agglomerates easy to be opened by mechanical force. At the same time, the dispersant aid further forms a flexible space protection film on the surface of the wetted particles. This film can effectively buffer the impact of the ball milling medium on the particles, reduce the direct and rigid collision between the particles, so as to guide the mechanical energy to be more converted into plastic deformation and rolling polishing of the particles, rather than causing cold welding or breaking. With the aid of this composite dispersing system and the optimized ball milling parameters, the TC4 irregular coarse powder can be efficiently shaped into near-spherical particles with high sphericity and smooth surface, and the physical properties such as Hall flow rate and loose density are significantly improved, which fully meets the stringent requirements of advanced additive manufacturing equipment on powder fluidity.

[0020] 2. The whole technical scheme of the application not only realizes good morphology of the powder, but also excellently controls the chemical purity, especially the content of key interstitial elements. This effect benefits from the fine design of the whole process from dispersant selection to post-treatment process. First, each component of the dispersant is a pure organic matter, which does not contain and is not easy to decompose impurity elements such as sulfur and phosphorus harmful to titanium alloy. Second, the adsorption layer formed by the dispersant on the surface of the particles isolates the powder from the limited air in the milling tank to some extent, providing in-situ protection. Most importantly, the post-treatment process of vacuum filtration separation combined with two-stage vacuum drying defined in the claim of the application provides a reliable path for removing the dispersant and ensuring purity. The process first removes most of the alcohol solvents and surfactants at a relatively low vacuum temperature, and then completely removes the dispersant aid with high molecular weight and high boiling point at a higher vacuum temperature. The whole drying process is carried out under negative pressure, which effectively prevents the contact of the powder with oxygen in the hot state, ensures the complete volatilization of the organic matter without pyrolysis and carbonization. Therefore, the oxygen content and carbon content of the final TC4 powder can remain stable compared with the raw material before ball milling, and even be optimized through cleaning, which meets the strict requirements of high-end applications on material purity.

[0021] 3. The application provides a TC4 powder ball milling complete solution with strong specificity, wide process window and high stability. Since the dispersant formula is specially designed and optimized for the surface characteristics of TC4 powder and the ball milling working condition, it shows good adaptability to changes in process parameters. Within the ball milling speed, time, ball-to-material ratio and drying temperature and time range defined in the claims, the scheme can produce qualified powder with consistent performance, reducing the frequency and difficulty of fine-tuning of process parameters in production, improving production efficiency and batch stability. Compared with the general solution which needs to try various additive or process condition combinations, the application integrates the functions of wetting, dispersion, morphology control and purity protection into a simple and efficient system, simplifies the operation process, improves the controllability and repeatability of the process, and lays a solid technical foundation for large-scale, standardized preparation of high-performance TC4 titanium alloy powder for 3D printing. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 A surface active agent type high-efficiency dispersant preparation process flow chart for TC4 titanium alloy powder.

[0023] Figure 2 A scanning electron microscope (SEM) morphology comparison chart of the powders obtained in Example 3 and Comparative Example 1. Among them Figure 2 (a) is the SEM photo of the powder of Example 3: showing the TC4 powder prepared by using the dispersant and method of the application; the particles in the figure are obviously spherical, the surface is smooth, the outline is clear, and there are few satellite balls and adhesions. Figure 2 (b) is the SEM photo of the powder of Comparative Example 1 (magnification: 150x): showing the TC4 powder prepared by using only pure isopropanol as the medium; the particles in the figure are extremely irregular in shape, with sharp corners, and there are a large number of fine particles and serious agglomerates. DETAILED DESCRIPTION

[0024] The application will be further described in detail below in combination with examples and comparative examples, but the protection scope of the application is not limited to the following examples. The ratios described in the claims of the application are mass ratios unless otherwise specified; the room temperature refers to an ambient temperature of 10°C to 30°C.

[0025] Example 1: Preparation of dispersant This example provides a surface active agent type high-efficiency dispersant for TC4 titanium alloy powder.

[0026] Take 800 g of isopropyl alcohol and place it in a 1-liter glass reaction kettle. Under the condition of stirring at 300-500 r / min, add 3.5 g of stearic acid to the reaction kettle. Raise the water bath temperature of the reaction kettle to 65℃, and continue stirring at this temperature for about 30 minutes until the stearic acid is completely dissolved, obtaining a clear and transparent solution. Then, add 196.5 g of paraffin wax with an average molecular weight of about 400 to the solution. Keep the water bath temperature at 65℃, and continue stirring for 2 hours until the system presents a uniform, stable milky white viscous liquid. Stop heating and naturally cool to room temperature, thereby obtaining about 1000 g of the dispersant of the present application, which is sealed and stored for later use. It is calculated that the mass percentage of isopropyl alcohol in the dispersant is 80.0%, the mass percentage of stearic acid is 0.35%, and the mass percentage of paraffin wax is 19.65%.

[0027] Example 2: Preparation of a dispersant This example provides another kind of surfactant type high-efficiency dispersant for TC4 titanium alloy powder.

[0028] Take 720 g of ethanol and place it in a container. Under the condition of stirring at 300-500 r / min, add 4.0 g of oleic acid and stir at room temperature until the mixture is uniformly mixed. Then, add 276 g of polyethylene wax with an average molecular weight of about 2500. Heat the mixture to 80℃, and use a homogenizing emulsifier to shear stir at a high speed of 1500-2000 r / min for 3 hours at this temperature, and keep the system temperature stable at 80℃±5℃ during the stirring process, forming a uniform paste. After cooling to room temperature, about 1000 g of the dispersant is obtained, in which the mass percentage of ethanol is 72.0%, the mass percentage of oleic acid is 0.4%, and the mass percentage of polyethylene wax is 27.6%.

[0029] Example 3: Preparation of spherical TC4 titanium alloy powder This example details the preparation of spherical TC4 titanium alloy powder using the dispersant and method of the present application, and tests the performance thereof.

[0030] (I) Preparation process Figure 1 ) Step 1: Preparation of raw materials Take the TC4 titanium alloy coarse powder prepared by the gas atomization method, crush it by the hydrogenation-dehydrogenation process, and use a standard sieve to screen it, and select the irregular TC4 alloy powder with a particle size of 45 μm to 150 μm as the raw material powder.

[0031] Step 2: Loading and ball milling 1. Weigh the raw materials: accurately weigh 100.0 g of the TC4 raw material powder obtained in step 1.

[0032] 2. Preparation of grinding balls: Select three kinds of stainless steel grinding balls with diameters of 6 mm, 10 mm and 15 mm, respectively, mix them in a quantity ratio of about 2:3:1, and make the total mass reach 400.0 g. The mass ratio of grinding balls to raw material powder is 4:1.

[0033] 3. Addition of dispersant: Measure 150.0 g of the dispersant prepared in Example 1 (i.e. 150% of the mass of the raw material powder).

[0034] 4. Canning: Put the above-mentioned raw material powder, mixed stainless steel grinding balls and dispersant into a ball mill tank with a volume of 2 liters for a planetary ball mill made of stainless steel 316, and seal it in a vacuum sealed manner to prevent air from entering.

[0035] 5. Ball milling: Seal the ball mill tank and install it on the planetary ball mill. Set the planetary revolution speed to 200 revolutions per minute. Use intermittent ball milling mode: first continuously ball mill for 30 minutes, then stop for 5 minutes to facilitate heat dissipation, which is one cycle. Repeat this cycle 4 times, for a total effective ball milling time of 2 hours.

[0036] Step three: post-treatment 1. Solid-liquid separation: After ball milling, transfer all the materials in the ball mill tank to a Buchner funnel and use a vacuum filtration device for solid-liquid separation. The separated solid powder is washed twice with a small amount of anhydrous ethanol to wash off the residual dispersant on the surface.

[0037] 2. Vacuum drying: Lay the washed wet powder flat on a material tray and put it into a vacuum drying oven.

[0038] First stage drying: Under the condition of a vacuum degree ≤ 1 x 10 -2 Pa, set the drying temperature to 70°C and the drying time to 6 hours.

[0039] Second stage drying: After the first stage drying is completed, do not take out the powder, directly adjust the temperature of the vacuum drying oven to 100°C, and continue drying for 3 hours.

[0040] 3. Cooling and collection: After the drying program is completed, turn off the heating and let the powder cool naturally to room temperature in a vacuum environment. Take it out and you get the spherical TC4 titanium alloy powder finished product.

[0041] (II) Performance test and results The spherical TC4 titanium alloy powder prepared is subjected to the following performance tests, and the test methods and results are as follows: 1. Morphology and sphericity observation: The powder morphology is observed by scanning electron microscope. For example, Figure 2(a) As shown, the powder particles are obviously spheroidal, with smooth surface and few satellite particles and agglomerated particles. 200 particles were randomly selected, and their projected area and perimeter were measured using image analysis software, and the sphericity (defined as the ratio of the perimeter of a circle with the same projected area as the particle to the actual projected perimeter of the particle) was calculated, with an average value of 0.91.

[0042] 2. Flowability test: According to GB / T 1482-2010 standard, the flowability of the powder was measured using Hall flowmeter. 50.0 g of the powder was weighed, and the time for passing through the standard funnel was 36.8 seconds.

[0043] 3 、 Bulk density test: According to GB / T 1479.1-2011 standard, the bulk density of the powder was measured using cylinder method, and the test result was 2.46 g / cm3.

[0044] 4. Chemical composition analysis: The oxygen and nitrogen contents in the powder were determined by inert gas pulse fusion-infrared / thermal conductivity method, and the carbon content was determined by high-frequency combustion-infrared absorption method. The test results were: oxygen content 0.152 wt.%, nitrogen content 0.012 wt.%, and carbon content 0.018 wt.%. Compared with the raw material powder before ball milling (oxygen content 0.148 wt.%, nitrogen content 0.011 wt.%, and carbon content 0.020 wt.%), the contents of key impurity elements did not significantly increase.

[0045] Example 4: Preparation of spheroidal TC4 titanium alloy powder (using the dispersant of Example 2) This example illustrates the preparation process using another formula dispersant, and the basic steps are the same as those of Example 3, and the main difference parameters are as follows: Raw material powder: HDH (hydrogenation-dehydrogenation) broken TC4 coarse powder with particle size of 45-200 μm, and the amount was 120.0 g.

[0046] Mill ball: stainless steel mill balls with diameters of 5 mm and 12 mm were mixed, and the total mass was 360.0 g (ball-to-material ratio of 3:1).

[0047] Dispersant: the dispersant prepared in Example 2 was used, and the addition amount was 240.0 g (200% of the mass of the raw material powder).

[0048] Ball milling parameters: rotation speed 180 revolutions / minute, intermittent mode 40 minutes of ball milling / 10 minutes of pause, 3 cycles, and total effective time 2 hours.

[0049] Drying parameters: first stage drying 75°C / 5 hours, and second stage drying 90°C / 4 hours.

[0050] The obtained powder has a sphericity of 0.89, a Hall flow rate of 39.5 s / 50g, a loose density of 2.41 g / cm3, and an oxygen content of 0.158 wt.%; the powder has a Hall flow rate of 39.5 s / 50g, which meets the requirements of high-end additive manufacturing on fluidity (allowable error ±2 s / 50g).

[0051] Comparative Example 1: using pure isopropanol as the ball milling medium This comparative example is used to illustrate the effect of not using the complex dispersant of the present application.

[0052] Except that the dispersant is replaced by an equal mass (150.0 g) of pure isopropanol, the remaining raw materials, equipment, ball milling parameters, and post-treatment steps are exactly the same as in Example 3.

[0053] After ball milling, obvious powder agglomeration and sedimentation can be seen in the slurry Figure 2 (b). The final obtained powder has poor sphericity and still has a large number of irregular edges and porous agglomerates, with an average sphericity of only 0.68. The powder has poor fluidity, with a Hall flow rate of more than 120 seconds / 50g (part of the powder cannot flow naturally). Due to the lack of an effective protective layer, the oxygen content of the powder increases to 0.189 wt.%.

[0054] Comparative Example 2: binary dispersant system lacking the dispersant aid paraffin This comparative example is used to illustrate the consequences of lacking the dispersant aid component.

[0055] A dispersant containing only isopropanol 99.65% and stearic acid 0.35% is prepared at a mass ratio of 150.0 g. Using this dispersant, ball milling is carried out under the same conditions and steps as in Example 3.

[0056] During the ball milling process, the powder dispersion state is initially acceptable, but with the passage of time, fine powder agglomeration gradually occurs. The sphericity of the final powder is improved to 0.82, but SEM shows that the particle surface is relatively rough, and there is a phenomenon of a large number of fine powder adhering to the large particles (satellite balls). Due to the lack of paraffin, the powder lacks flexible protection during the drying stage, and some particles bridge due to capillary forces, resulting in a fluidity of only 52.4 seconds / 50g.

[0057] Comparative Example 3: using a conventional drying process This comparative example is used to illustrate the importance of two-stage vacuum drying in the post-treatment process.

[0058] The ball milling and solid-liquid separation steps are exactly the same as in Example 3. However, in the drying stage, it is changed to one-time drying for 10 hours at 100°C in an ordinary drying oven in an air atmosphere.

[0059] The obtained powder is dark in color, and the sphericity is acceptable (0.88), but the chemical analysis shows that the oxygen content is significantly increased to 0.235 wt.%, which is much higher than 0.152 wt.% of the two-stage drying process in vacuum of the present application (Example 3), and exceeds the upper limit of 0.2% required for high-end additive manufacturing, proving that thermal drying in air environment can introduce serious oxidation. At the same time, part of the organic residues may be carbonized, resulting in a slight increase in carbon content.

[0060] Effect analysis By comparing the results of the examples and the comparative examples, it can be clearly seen that: 1. Examples 3 and 4 prove that by using the complex dispersant and complete preparation method claimed in the present application, irregular TC4 coarse powder can be successfully shaped into spherical powder with high sphericity, good flowability, and controllable impurity content, fully meeting the requirements of high-end additive manufacturing.

[0061] 2. Comparative Example 1 shows that using only a single alcohol solvent cannot provide sufficient dispersion and spheroidization force, and the powder performance is seriously substandard, highlighting the necessity of the surfactant and the co-dispersant in the complex system of the present application.

[0062] 3. Comparative Example 2 shows that without the co-dispersant (paraffin, polyethylene wax, or polyethylene glycol, etc.), the stability of the dispersion system is insufficient, and cannot effectively prevent the secondary agglomeration of particles and the generation of satellite balls during the later stage of ball milling and the drying process, resulting in a decrease in powder flowability, proving the synergistic effect of the ternary components.

[0063] 4. Comparative Example 3 shows that even if the correct dispersant is used, if the post-treatment process is improper (non-vacuum environment), the powder will be oxidized and contaminated, and the purity index will deteriorate, thereby confirming the key role of the two-stage drying under vacuum defined in the present application in ensuring the chemical purity of the final product.

[0064] In summary, the technical solutions of the present application are interrelated and synergistic, and together achieve the beneficial effect of improving the sphericity and flowability of TC4 titanium alloy powder while strictly controlling its chemical purity, and this effect has been fully verified by the examples. The comparative examples prove the non-obviousness and importance of the technical features of the present application. It should be noted that the above examples are used to illustrate the technical solutions of the present application, but not to limit the present application. Within the scope defined by the claims, those skilled in the art can make appropriate modifications and adjustments to the specific embodiments of the present application.

Claims

1. A surface-active high-efficiency dispersant for TC4 titanium alloy powder, comprising the following components in percentage by mass: 70-85% of an alcohol solvent; 0.2-0.4% of an anionic surfactant selected from stearic acid, oleic acid or sodium dodecyl benzene sulfonate; and 14.6-29.8% of a co-dispersant selected from paraffin, petroleum ether, polyethylene glycol or polyethylene wax, and the co-dispersant has an average molecular weight of 300-2500. The alcohol solvent is one of isopropyl alcohol, ethanol or methanol, and has a mass percentage of 70-85%. The co-dispersant is paraffin, petroleum ether, polyethylene glycol or polyethylene wax, and the co-dispersant has an average molecular weight of 86-500. 4.Use of the surface-active high-efficiency dispersant for TC4 titanium alloy powder according to any one of claims 1-3 in the preparation of TC4 titanium alloy powder by wet planetary ball milling.

2. The surface active high-efficiency dispersant for TC4 titanium alloy powder according to claim 1, characterized in that, The method comprises the following steps:

3. The surface-active, high-efficiency dispersant for TC4 titanium alloy powder according to claim 1 or 2, characterized in that, (1) placing hydrogenated and dehydrogenated broken TC4 titanium alloy coarse powder, stainless steel grinding balls and the dispersant according to any one of claims 1-3 in a ball mill jar of a planetary ball mill, and performing wet ball milling, wherein the dispersant is added in an amount of 150-250% of the mass of the TC4 titanium alloy coarse powder, the mass ratio of the stainless steel grinding balls to the TC4 titanium alloy coarse powder is 3:1-5:1, the diameter of the stainless steel grinding balls is 5-15 mm, and the mass ratio of grinding balls with different diameters is 1:2:3-3:2:1; (2) after the ball milling is completed, performing solid-liquid separation on the material in the ball mill jar to obtain a solid powder; 5. A method for preparing a quasi-spherical TC4 titanium alloy powder, characterized in that, The wet ball milling is performed in an intermittent manner, specifically, the ball milling is operated for 10-60 minutes, and then paused for 2-10 minutes. The stainless steel grinding balls are composed of at least two grinding balls with different diameters. The first-stage drying is performed for 2-12 hours, and the second-stage drying is performed for 1-8 hours. (3) the solid powder is dried in two stages under vacuum, the first stage being at a temperature of 60-80°C and the second stage being at a temperature of 80-120°C, wherein the vacuum is < 1 x 10 -2 Pa.

6. The method of claim 5, wherein the spherical TC4 titanium alloy powder is prepared by the steps of: preparing a TC4 titanium alloy powder; and performing a ball milling process on the TC4 titanium alloy powder. The hydrogenated and dehydrogenated broken TC4 titanium alloy coarse powder has a particle size of 45-200 μm.

7. The method of claim 6, wherein the spherical TC4 titanium alloy powder is prepared by the steps of: preparing a TC4 titanium alloy powder; and performing a ball milling process on the TC4 titanium alloy powder. ​ 8. The method of claim 5, wherein the spherical TC4 titanium alloy powder is prepared by the steps of: preparing a TC4 titanium alloy powder; and performing a ball milling process on the TC4 titanium alloy powder. ​ 9. The method of claim 5, wherein the spherical TC4 titanium alloy powder is prepared by the steps of: preparing a TC4 titanium alloy powder; and performing a ball milling process on the TC4 titanium alloy powder. ​ 10. The method of claim 5, wherein the spherical TC4 titanium alloy powder is prepared by the steps of: preparing a TC4 titanium alloy powder; and performing a ball milling process on the TC4 titanium alloy powder. ​

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